The present invention relates to articles for protection of the patient as well as surgical personnel during laser surgery. In more detail, the present invention relates to a composite for use in making articles such as gloves, surgical drapes, aprons and other items of apparel for use in protecting both patient and surgical personnel from damaged tissue resulting from direct incidence of a laser on that tissue during surgery or from fire resulting from incidence of a laser on flammable materials.
Although most damage to the skin or other tissue from a laser is repairable, the extent of the damage varies depending upon the degree of absorption of the laser wavelength and the duration of exposure such that there is potential for serious damage. Adding to that potential is the fact that reflection of the laser beam is potentially as damaging as direct contact with the beam. Various safety measures are employed depending upon the surgical procedure to protect against such damage. For instance, a back drop is used behind the tissue being lased, when possible, and in the abdominal cavity, a wet wooden tongue blade, titanium rod or wet laparotomy sponge can be used to protect underlying tissue. Abdominal and cranial cavities are filled with sterile saline to absorb the energy of the beam. Non-involved, exposed tissue is covered with wet laparotomy sponges, four by fours, or cottonoids. Patients are restrained from movement, and beaded or other non-reflective instruments are used.
Fires can occur by ignition of a drape, endotracheal tube, or article of clothing, plastic, or rubber in the treatment area. On information and belief, none of the standard surgical drapes will resist impact from a laser beam, Precautions against fire include, for instance, the covering of surgical drapes with wet towels and/or laparotomy sponges, the wetting of all the drapes, sponges and gauzes used in the area of laser application, and the precautions listed above for protecting against laser burns.
The protection provided by even the most careful application of all of these precautions simply is not sufficient. Depending upon the wavelength, time of exposure, type of laser and several other factors, the laser is capable of vaporizing these "protective" articles in exactly the same manner as the tissue on which the laser is intended to be used. There is, therefore, a need for effective protective articles for use in the treatment area.
At least one attempt has been made to provide such an article. U.S. Pat. No. 4,601,286 is directed to an "Article for the Protection of Living Tissues", said to protect ". . . living tissue from damage due to exposure to lasers . . . ". That patent describes the use of a hydrogel in the form of a drape or dressing having an opening through which the laser light can pass to impinge on the portion of the tissue to be lased, the opening having a size and shape approximating that of the tissue site to be lased (col. 5, lines 13-20, 56-60). In practice, however, such an article does not protect against laser burns; at best, such articles may provide some protection against ignition because of the high water content of the hydrogel. Experimentation has shown that penetration of a twenty-five watt or greater laser through such articles is instantaneous; further, the hydrogels are clear, making them of limited use for argon lasers which "seek" color. Penetration of the laser through the hydrogel does not appear to depend on the thickness of the hydrogel--instead, the laser penetrates instantaneously no matter what the thickness. There is, therefore, still a need for a material from which effective protective articles can be made for use in laser surgery.